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///M3 Forum The BMW E46 ///M3 is the M version E46 and puts out an amazing 333 HP and 262 lb-ft of torque at stock specs! There are an amazing amount of modifications for both the coupe and convertible models so read up and get started modifying your cars today!

I recently had my tires changed to 245f/275r about three weeks ago, but I don't remember if this problem started before or only after the tire change. The left front brake disc seems to show quite a bit of uneven wear. There is no vibration on the highway when just driving, but when I sort of put my foot on the brake pedal, I do feel some mild vibration.
Only the left front brake disc shows uneven wear but the other three are fine.

Do you think there could be something with the tires? Or could be something else?

Pic of left front brake disc. The inner part sees fine but the outer part shows these lines wear.

Unlikely the tire change has anything to do with your brake issue.
There could be several thing going on: 1. Cracked pad. 2. Caliper hanging up (not completely releasing) 3. Bent guide pin allowing the caliper to become unsquare with the rotor. 4. Sticky guide pins keeping the caliper from sliding freely 5. Some debris caught between the caliper and the rotor.
You need to disassemble that side and investigate further.

I've seen all kinds of weird things happen, including cross-threaded caliper pins, rust on carrier so pads don't slide, and sticky calipers. I'd do a teardown and see if the pins and pads are sliding okay, and then also see if the piston is hanging up badly. If the piston is hanging up, then just get some new ones from bimmerworld along with a rebuild kit.

Not during the normal course of changing a tire, but who knows what they really did.... If you are going to return to the tire place to tell them you think that they did it you will have a slim chance of proving it; but I guess it is worth a try.
Don't be cheap in attempting to cut the rotor as BMW doesn't sanction it and that one looks like you would have to remove a lot of metal to get it flat. Buy a new one. The other side looks reasonably new so even though I don't reccommend it you might get away with just changing the one side. Usually they are changed in pairs per axle.

Tire shops have an extremely annoying habit of over-torquing wheel bolts when they put the wheels back on your car. They use a compressor-driven socket that puts the bolts on WAY too tight, and this can warp your rotors. If you cannot remove the bolts using a simple spanner, without the need to jump on it or use a mallet, they are on too tight.

When at speed, if I just slightly tap on the brake pedal, I do feel a pulsating stream on the brake pedal and on the steering wheel as well, but I wouldn't characterize it as vibration since that may be too strong. If I do stomp on it and brake hard, I don't really feel any vibration and it feels pretty solid and if there's any vibration , it's probably from the road surface. I think I can tell the difference if it comes from the rotor or the road because the rotor will give a more periodic vibration.

My guess is the brake pads are riding on the rotor which is causing the uneven line. This morning when I looked at the rotor surface closely, I saw a couple of pretty sharp cuts on the surface.

If the rotor is warped, then braking hard would feel the vibration the most I think but it doesn't seem to be the case. The car has about 100K miles so I am not sure if the previous owner ever did any maintenance on the brake calipers.

You need to take it apart and see im surprised your still driving it and have not even seen a shop or checked it out your self.

Every single person here is guessing until you take the wheel and caliper off.

Will soon but most likely at a shop. August is a three pay check month so the timing is very good.
and "Draghi just put a floor on the market". :-)
Also I have a set of springs and shocks so I plan to do them all at the same time.

I sure feel like an idiot. The problem was simple as re-torquing the bolts. All I did was loosen the bolts a bit, and re-torque at 88lbs-ft. I did this on Sunday and after driving for awhile, I didn't feel any vibration. I wasn't quite sure but after driving for two more days, I am pretty sure the vibration has gone away.

I mean these people are paid but if they can't get something as basic as torquing, I don't know what to say.

Machine or looks like replace rotors on both fronts. Inspect caliper slides and if piston seizing? Slides must have worked to get it to wear on the outside of rotor but rocks dont make that many grooves? New pads of course after rotor swap. Push piston into caliper till flush then watch as brake is stepped on. Not from tires for sure. Clean and antiseize slides.

So your problem was the lug bolts needed to be torqued to spec? Wow, didn't think over tightened lug bolts would cause that. I can't stand it when shops allow their employees to tighten lug nuts/bolts with air. Last couple times I've had a shop take off my wheels, I made sure to stand in and watch to make sure their using torque wrenches and anti seize to put the wheels back on.

So your problem was the lug bolts needed to be torqued to spec? Wow, didn't think over tightened lug bolts would cause that. I can't stand it when shops allow their employees to tighten lug nuts/bolts with air. Last couple times I've had a shop take off my wheels, I made sure to stand in and watch to make sure their using torque wrenches and anti seize to put the wheels back on.

I think the M3 rotors are probably lighter, thinner, and maybe a bit softer and are designed for performance and light weight so they are probably more sensitive to over-torqued. I never had this issue before on any of my previous "low end" cars.

So your problem was the lug bolts needed to be torqued to spec? Wow, didn't think over tightened lug bolts would cause that. I can't stand it when shops allow their employees to tighten lug nuts/bolts with air. Last couple times I've had a shop take off my wheels, I made sure to stand in and watch to make sure their using torque wrenches and anti seize to put the wheels back on.